The move towards a circular economy represents an urgent need for production and distribution systems. For this reason, traditional supply chains must rearrange their structures and configurations to reduce virgin material extraction, as well as production and end-of-life products that are sent to landfill. However, many questions regarding the dynamic behavior of circular supply chains remain unsolved. The aim of this work is to contribute to the literature on circular supply chains by investigating their dynamics when there are several reverse loops, i.e., the products delivered to the final customer have been either produced from virgin materials, by the remanufacturing of end-of-life products, or by the use of by-products generated in another supply chain. Using a full factorial design of experiments and a difference equation modelling approach, a wide range of supply chain scenarios with different return and by-product usage rates are analyzed, and their dynamic and economic performance is evaluated. Our results suggest that there is a combined effect of the return rate and the by-product rate on the dynamic behavior of the supply chain. When their combination exceeds a stability threshold, the order amplification disappears, at the expense of unmanageable inventories. However, they also show that, below this threshold, circular supply chains can outperform traditional ones.

中文翻译：

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关于结合副产品和报废退货的循环供应链中的牛鞭效应


向循环经济的转变代表了对生产和分销系统的迫切需求。因此，传统供应链必须重新安排其结构和配置，以减少原始材料的提取，以及送往垃圾填埋场的生产和报废产品。然而，关于循环供应链动态行为的许多问题仍未解决。这项工作的目的是通过研究存在多个反向循环时的动态来为循环供应链的文献做出贡献，即交付给最终客户的产品要么由原始材料生产，要么通过报废产品的再制造，要么通过使用另一个供应链中产生的副产品。使用全因子实验设计和差分方程建模方法，分析了具有不同退货和副产品使用率的各种供应链情景，并评估了它们的动态和经济绩效。我们的结果表明，退货率和副产品率对供应链的动态行为存在综合影响。当它们的组合超过稳定阈值时，订单放大就会消失，代价是无法管理的库存。然而，它们也表明，低于这个阈值，循环供应链的表现可以优于传统供应链。